The Complete Characterization of a Rhodium Lewis Acid−Dipolarophile Complex as an Intermediate for the Enantioselective Catalytic 1,3-Dipolar Cycloaddition of <i>C</i>,<i>N</i>-Diphenylnitrone to Methacrolein
作者:Daniel Carmona、M. Pilar Lamata、Fernando Viguri、Ricardo Rodríguez、Luis A. Oro、Ana I. Balana、Fernando J. Lahoz、Tomás Tejero、Pedro Merino、Santiago Franco、Isabel Montesa
DOI:10.1021/ja031995z
日期:2004.3.1
The 1,3-dipolar cycloaddition reaction of C,N-diphenylnitrone with methacrolein is efficiently catalyzed by the rhodium diphosphine compound (SRh,RC)-[(eta5-C5Me5)Rh(R-Prophos)(H2O)](SbF6)2 [R-Prophos = (R)-(+)-1,2-bis(diphenylphosphino)-propane, 1.SbF6]; the asymmetric catalytic process occurs with reversal of regioselectivity, perfect endo selectivity, and up to 92% ee. The complete (NMR and X-ray
C,N-二苯基硝酮与甲基丙烯醛的 1,3-偶极环加成反应由铑二膦化合物 (SRh,RC)-[(eta5-C5Me5)Rh(R-Prophos)(H2O)](SbF6)2 有效催化[R-Prophos = (R)-(+)-1,2-双(二苯基膦基)-丙烷,1.SbF6];不对称催化过程发生逆转区域选择性、完美的内向选择性和高达 92% 的 ee。所涉及的中间体 (SRh,RC)-[(eta5-C5Me5)Rh(R-Prophos)(methacrolein)](SbF6)2 (7.SbF6) 的完整(NMR 和 X 射线分析)表征使我们能够解释观察到的选择性。